665440002 has 128 divisors (see below), whose sum is σ = 1643673600. Its totient is φ = 198614592.

The previous prime is 665439997. The next prime is 665440031. The reversal of 665440002 is 200044566.

It is a happy number.

665440002 is a `hidden beast` number, since 6 + 654 + 4 + 0 + 0 + 0 + 2 = 666.

665440002 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3846388 + ... + 3846560.

It is an arithmetic number, because the mean of its divisors is an integer number (12841200).

Almost surely, 2^665440002 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665440002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (821836800).

665440002 is an abundant number, since it is smaller than the sum of its proper divisors (978233598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665440002 is a wasteful number, since it uses less digits than its factorization.

665440002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389 (or 383 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 665440002 is about 25796.1237785835. The cubic root of 665440002 is about 873.0443406347.

Adding to 665440002 its reverse (200044566), we get a palindrome (865484568).

It can be divided in two parts, 6654 and 40002, that added together give a 6-th power (46656 = 6⁶).

The spelling of 665440002 in words is "six hundred sixty-five million, four hundred forty thousand, two".